<?php
/**
 * @package AKSRT
 */

namespace AKSRT\Payment;

defined('ABSPATH') || exit;

/**
 * 站内余额支付网关（内置实现）。
 *
 * 仅扣现金钱包（\AKSRT\Credits\Balance / pay_balance_s），不再回退到积分。
 */

class BalanceGateway implements GatewayInterface {

    public function get_id(): string {
        return 'balance';
    }

    public function get_name(): string {
        return __('站内余额', 'aksrt');
    }

    public function is_configured(): bool {
        // Cash wallet only — do not treat points as 余额.
        if (!class_exists('\AKSRT\Credits\Balance') || !\AKSRT\Credits\Balance::enabled()) {
            return false;
        }
        if (class_exists('\AKSRT\Settings\PaymentRuntime')) {
            return \AKSRT\Settings\PaymentRuntime::is_gateway_enabled('balance');
        }
        return true;
    }

    public function create_payment(array $order): array {
        $user_id = (int) ($order['user_id'] ?? 0);
        $amount = round((float) ($order['amount'] ?? 0), 2);
        $order_number = (string) ($order['order_number'] ?? '');

        if (!class_exists('\AKSRT\Credits\Balance') || !\AKSRT\Credits\Balance::enabled()) {
            return ['success' => false, 'message' => __('余额功能未启用', 'aksrt')];
        }
        if ($user_id <= 0) {
            return ['success' => false, 'message' => __('请先登录', 'aksrt')];
        }
        $balance = \AKSRT\Credits\Balance::balance($user_id);
        if ($balance < $amount) {
            return ['success' => false, 'message' => __('余额不足', 'aksrt')];
        }
        $result = \AKSRT\Credits\Balance::deduct(
            $user_id,
            $amount,
            'order_payment',
            ['type' => 'order', 'id' => 0, 'order' => $order_number],
            sprintf(__('订单 %s 支付', 'aksrt'), $order_number)
        );
        if (is_wp_error($result)) {
            return ['success' => false, 'message' => $result->get_error_message() ?: __('扣款失败', 'aksrt')];
        }
        return [
            'success'        => true,
            'transaction_id' => 'BAL_' . ($order_number !== '' ? $order_number : (string) time()),
            'message'        => __('余额支付成功', 'aksrt'),
        ];
    }

    public function verify_callback(\WP_REST_Request $request): array {
        // Balance payment is synchronous — no callback needed
        return ['success' => false, 'message' => __('余额支付无需回调验证', 'aksrt')];
    }

    public function query_status(string $order_number): array {
        $order_repo = OrderRepository::get_instance();
        $order = $order_repo->get($order_number);

        if (!$order) {
            return ['success' => false, 'message' => __('订单不存在', 'aksrt')];
        }

        return [
            'success'        => true,
            'status'         => $order['status'],
            'transaction_id' => $order['payment_transaction_id'] ?? '',
        ];
    }

    public function refund(string $order_number, float $amount, string $request_id = ''): array {
        $order_repo = OrderRepository::get_instance();
        $order = $order_repo->get($order_number);

        if (!$order) {
            return ['success' => false, 'message' => __('订单不存在', 'aksrt')];
        }

        $user_id = (int) $order['user_id'];
        $amount = round((float) $amount, 2);

        if (!class_exists('\AKSRT\Credits\Balance') || !\AKSRT\Credits\Balance::enabled()) {
            return ['success' => false, 'message' => __('余额功能未启用', 'aksrt')];
        }

        $request_id = sanitize_text_field($request_id);
        $refund_key = $request_id !== '' ? $request_id : 'order:' . $order_number;
        $lock_key   = 'aksrt_balance_refund_' . hash('sha256', $refund_key);
        $existing   = get_option($lock_key, []);
        if (is_array($existing) && ($existing['status'] ?? '') === 'succeeded') {
            return [
                'success'   => true,
                'refund_id' => 'BAL_REF_' . $order_number,
                'message'   => __('退款已处理（幂等）', 'aksrt'),
            ];
        }
        if (is_array($existing) && ($existing['status'] ?? '') === 'pending') {
            return ['success' => false, 'status' => 'pending', 'message' => __('退款正在处理中，请稍后查询', 'aksrt')];
        }

        $marker = ['status' => 'pending', 'token' => wp_generate_uuid4(), 'created_at' => time()];
        if (!add_option($lock_key, $marker, '', false)) {
            return ['success' => false, 'status' => 'pending', 'message' => __('退款正在处理中，请稍后查询', 'aksrt')];
        }

        try {
            $result = \AKSRT\Credits\Balance::add(
                $user_id,
                $amount,
                'order_refund',
                ['type' => 'order', 'order' => $order_number, 'request_id' => $request_id],
                sprintf(__('订单 %s 退款', 'aksrt'), $order_number)
            );
            if (is_wp_error($result)) {
                delete_option($lock_key);
                return ['success' => false, 'message' => $result->get_error_message() ?: __('退款失败', 'aksrt')];
            }
            update_option($lock_key, [
                'status'       => 'succeeded',
                'refund_id'    => 'BAL_REF_' . $order_number,
                'completed_at' => time(),
            ], false);
            return ['success' => true, 'refund_id' => 'BAL_REF_' . $order_number, 'message' => __('退款成功', 'aksrt')];
        } catch (\Throwable $e) {
            delete_option($lock_key);
            return ['success' => false, 'message' => $e->getMessage()];
        }
    }
}